Antiskid device for motor vehicle tires

Claim 1

An antiskid device mountable on motor vehicle tires and comprising an inner fastening adapted to engage the inside of a tire, said inner fastening in both its unmounted and mounted or fitted state on the tire normally having an essentially circular form and comprising a central mounting portion having free ends swivably connected to side part portions by swivel joints, the side part portions, for facilitating fitting the inner fastening to the inside of the tire, being radially outwardly movable relative to the central mounting portion when said inner fastening is in the normal essentially circular form and being normally pretensioned by spring means in both its unmounted and mounted or fitted state to automatically urge said side part portions into closed form, the central mounting portion comprising at least two portions swivably connected by a swivel joint for movement toward one another and being also pretensioned by spring means in a radially inward direction so that the inner fastening, constituted of said central mounting portion and said side part portions, is normally in said essentially circular form in both its unmounted and mounted or fitted state, all said spring means comprising leg springs having an intermediate part supported on the swivel joints and outer leg parts supported on associated of said central and side part portions of said inner fastening, and stop means for said swivel joints and said portions interconnected thereby for locking against further swivelling movement of said portions in a first direction beyond said essentially circular form one said essentially circular form is attained and in a second direction to limit movement of said portions when said side part portions are moved in a direction away from said essentially circular form.